EFFECT OF LINK SLAB ON SEISMIC RESPONSE OF TWO SPAN STHAIGHT AND SKEW BRIDGES

Highway bridges arc frequently constructed as simple span structures with steel or concrete girders and a cast-in-place concrete deck. spanning trom am: pier to anoilier. At each end or the simple span deck. a joint is provided for deck movement due to temperatu re. shrinkage. and creep. Bridge deck joints are expensive and pose many problems with regard to bridge maintenance. Elimination or deckj oints at the support of multi-span bridges has been the subj ect or recent studies. Recent researches have led to the development or a design concept and approach lor j ointlcss hridg S where the expansion j oints ar replaced with continuous link slabs. Further studies have indicated the proper performance or such bridges under service loading conditions. This paper presents analytical stud: of seismic behavior and response of a two spun bridge connected by link slabs. Three dimensional finite element analyses or straight and skew bridges with skew angles varying from 15 to 60 degrees is performed. Both linear time history , nd response spectrum analyses method are carried out in order to investigate the response or the bridge. The results indicate that the force and displacement demands of the interio r bent maybe reduced considerably. if link slab i:; used in the middle of the bridge instead or an expansionjoint.